package com.sites.common.kit;

import java.net.InetAddress;
import java.net.UnknownHostException;

import javax.servlet.http.HttpServletRequest;

/**
 * IP工具类
 * 来自网络：https://blog.csdn.net/linchack/article/details/81066028
 * 
 * @author zyg
 * 2020年8月1日 下午11:10:08
 */
public class IpKit {

	/**
	 * 获取用户真实IP地址，不使用request.getRemoteAddr();的原因是有可能用户使用了代理软件方式避免真实IP地址, 参考文章：
	 * http://developer.51cto.com/art/201111/305181.htm
	 * 
	 * 可是，如果通过了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP值，究竟哪个才是真正的用户端的真实IP呢？
	 * 答案是取X-Forwarded-For中第一个非unknown的有效IP字符串。
	 * 
	 * 如：X-Forwarded-For：192.168.1.110, 192.168.1.120, 192.168.1.130,
	 * 192.168.1.100
	 * 
	 * 用户真实IP为： 192.168.1.110
	 * 
	 * @param request
	 * @return
	 */
	public static String getIpAddress(HttpServletRequest request) {
		String ipAddress = request.getHeader("x-forwarded-for");
		if (ipAddress == null || ipAddress.length() == 0
				|| "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("Proxy-Client-IP");
		}
		if (ipAddress == null || ipAddress.length() == 0
				|| "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("WL-Proxy-Client-IP");
		}
		if (ipAddress == null || ipAddress.length() == 0
				|| "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getRemoteAddr();
			if (ipAddress.equals("127.0.0.1")
					|| ipAddress.equals("0:0:0:0:0:0:0:1")) {
				// 根据网卡取本机配置的IP
				InetAddress inet = null;
				try {
					inet = InetAddress.getLocalHost();
					ipAddress = inet.getHostAddress();
				} catch (UnknownHostException e) {
					e.printStackTrace();
				}
			}
		}
		// 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
		if (ipAddress != null && ipAddress.length() > 15) { // "***.***.***.***".length()
															// = 15
			if (ipAddress.indexOf(",") > 0) {
				ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
			}
		}
		return ipAddress;
	}

	/**
	 * 获取本地IP
	 * 
	 * @return
	 * @throws UnknownHostException
	 */
	public static String getLocalIP() throws UnknownHostException {
		String localIP = "";
		InetAddress addr = (InetAddress) InetAddress.getLocalHost();

		localIP = addr.getHostAddress().toString();
		return localIP;
	}

}
